## 📝 Introduction This repository provides the pretrained model weights for **NEVC-1.0**, which integrates contributions from **EHVC (Efficient Hierarchical Reference and Quality Structure for Neural Video Coding)** — one of the core components of the framework. **EHVC** introduces a hierarchical reference and quality structure that significantly improves both compression efficiency and rate–distortion performance. The corresponding code repository can be found here: [NEVC-1.0-EHVC](https://github.com/bytedance/NEVC). Key designs of **EHVC** include: - **Hierarchical multi-reference:** Resolves reference–quality mismatches using a hierarchical reference structure and a multi-reference scheme, optimized for low-delay configurations. - **Lookahead mechanism:** Enhances encoder-side context by leveraging forward features, thereby improving prediction accuracy and compression. - **Layer-wise quantization scale with random quality training:** Provides a flexible and efficient quality structure that adapts during training, resulting in improved encoding performance. --- ## 🔧 Models EHVC uses two models: the intra model and the inter model. - The **intra model** handles intra-frame coding. - The **inter model** is responsible for inter-frame (predictive) coding. ### Intra Model The main contributions of NEVC-1.0 focus on inter coding. For intra coding, we directly adopt the pretrained model **`cvpr2023_image_psnr.pth.tar`** from [DCVC-DC](https://github.com/microsoft/DCVC/blob/main/DCVC-family/DCVC-DC/checkpoints/download.py), without further training. ### Inter Model The inter model of NEVC-1.0 is provided at **`/models/nevc1.0_inter.pth.tar`**. The architecture of the inter model is illustrated below:

--- ## 📊 Experimental Results ### Objective Comparison

**BD-Rate (%) comparison for PSNR** Anchor: VTM-23.4 LDB. All codecs tested with 96 frames and intra-period = 32. BD-Rate 96F32G

**Rate–Distortion curves** on HEVC B, HEVC C, UVG, and MCL-JCV datasets. Tested with 96 frames and intra-period = 32. RD curves 96F32G

**BD-Rate (%) comparison for PSNR** Anchor: VTM-23.4 LDB. All codecs tested with full sequences and intra-period = -1. BD-Rate allF-1G

**Rate–Distortion curves** on HEVC B, HEVC C, UVG, and MCL-JCV datasets. Tested with full sequences and intra-period = -1. RD curves allF-1G

--- ## 📜 Citation If you find **NEVC-1.0** useful in your research or projects, please cite the following paper: - **EHVC: Efficient Hierarchical Reference and Quality Structure for Neural Video Coding** Junqi Liao, Yaojun Wu, Chaoyi Lin, Zhipin Deng, Li Li, Dong Liu, Xiaoyan Sun. *Proceedings of the 33rd ACM International Conference on Multimedia (ACM MM 2025).* ```bibtex @inproceedings{liao2025ehvc, title={EHVC: Efficient Hierarchical Reference and Quality Structure for Neural Video Coding}, author={Liao, Junqi and Wu, Yaojun and Lin, Chaoyi and Deng, Zhipin and Li, Li and Liu, Dong and Sun, Xiaoyan}, booktitle={Proceedings of the 33rd ACM International Conference on Multimedia}, year={2025} } ``` --- ## 🙌 Acknowledgement The intra model of this project is based on [DCVC-DC](https://github.com/microsoft/DCVC/blob/main/DCVC-family/DCVC-DC/checkpoints/download.py).